This invention relates to an apparatus for treating a shoe sole, and more particularly to an apparatus for splitting the marginal edge portions of a shoe sole.
Heretofore, the marginal edge portion of an outer shoe sole has been split or skived to facilitate securing the marginal edge portion of the outer shoe sole to the inturned marginal edge portions of the shoe upper. The marginal edge portion of the outer shoe sole is cut or skived to reduce its thickness so that the inturned marginal edge portion of the shoe upper may be placed and adhesively secured to the marginal edge portion of the sole. Accordingly, the inner surface of the central portion of the outer sole will be substantially flush with the inner surfaces of the inturned upper marginal edge portions. Thus, when an insole is placed within the shoe, the insole will fit substantially level and smooth on top of the inner surface of the central portion of the outer sole and against the inner surface of the marginal edge portions of the upper. Consequently, there will be no ridges along the margin of the inner sole which will be uncomfortable to the foot of the wearer of the completed shoe.
After the marginal edge portion of the inner or upper surface of the outer shoe sole is cut, split, or skived, the skived portion is primed with an adhesive primer solution. A shoe adhesive is then applied on top of the primed, skived, marginal edge portion for securing to the inturned marginal edge portions of the upper.
The skiving of the marginal edge portions of the shoe sole also tends to roughen the marginal edge portions to provide a better bond for the primer and the adhesive.
Heretofore, the steps of skiving the marginal edge portion of the shoe sole and the priming of the skived edge portion have been performed separately. The priming has been done manually, and the skiving operation has been carried out semi-automatically.
One form of sole splitting apparatus previously used is schematically disclosed in FIG. 11. The prior sole splitting apparatus includes a pair of upper and lower rollers stationarily mounted for rotation opposing each other at a sole splitting station. Behind the rollers and extending between the rollers is a fixed knife having a transverse cutting edge. In advance of the splitting station is a fixed bed plate upon which the shoe sole is placed. A sole pattern, having an external profile or periphery identical to the periphery of the shoe sole, is placed in vertical alignment on top of the shoe sole. The pattern has a central opening having a profile substantially similar to the outer profile of the shoe sole, but smaller in size, to provide a marginal rim in the pattern resting against the rim or marginal portion of the shoe sole. The upper roller is solid steel, while the lower roller has a semi-resilient surface, such as a polyurethane surface. The matched pattern and shoe sole are then fed by hand between the driven rollers until the end of the shoe sole engages the knife. The relative levels of the shoe sole and the knife are such that the knife cuts or skives only the marginal portion of the shoe sole, since the central portion is forced upwardly into the pattern cavity or opening by the urethane surface of the lower roller.
The disadvantage of the prior art apparatus disclosed in FIG. 11 is that after the pattern and shoe have passed through the splitting station, an operator must separate the pattern from the shoe sole, discharge the cut shoe sole, retrieve the pattern and return it by hand to the advance or feed side of the splitting station where the pattern is matched with a subsequent sole in preparation for feeding into the splitting station.
Other examples of machines for skiving or cutting shoe parts, and particularly soles, are disclosed in the following U.S. Pats. Nos.: 467,441, Scott, Jan. 19, 1892; 1,315,367, Jacquemin, Sept. 9, 1919; 1,382,689, Stewart, June 28, 1921; 1,706,485, Furber, Mar. 26, 1929; 2,141,134, Gillis, Dec. 20, 1938; 2,217,753, Johnson, Oct. 15, 1940; 2,241,478, Remington, May 13, 1941; 2,378,940, MacKenzie, June 26, 1945.
The patents to Scott, Stewart, Gillis and Johnson disclose skiving machines in which a pair of opposed rollers are used to feed the shoe part toward the stationary knife blade, and in which one of the rollers is a matrix roller having a depression formed in the surface of the matrix roller for receiving the portion of the shoe part which is not to be cut.
The patents to Furber and Gillis disclose reciprocating feed slides for feeding a flat shoe part to the skiving or cutting mechanism.
The Remington U.S. Pat. No. 2,241,478 discloses the concept of utilizing a matrix plate having cavities in communication with a suction device for holding down portions of the shoe parts not to be cut. However, Remington utilizes a disc type knife which is moved across the matrix plate for skiving the raised portions of the shoe part.
MacKenzie discloses a sole chamfering machine in which the edges of the sole are chamfered by a knife and the cut edges are coated with a cement. However, it would appear that the sole has to be guided by hand beneath the cutting and cement applying tools.